History: Jeremy Fitzoliver is generally remembered by The Doctor as a well-intentioned but frustrating incompetent would-be companion, who originally became involved with The Doctor’s
adventures in UNIT when Sarah
Jane Smith requested a photographer for her current story and
her editor, uninterested in the story in question, sent Jeremy, an
upper-class twit who barely knew which way to hold the camera, instead
of a more experienced photographer. However, since the story in question
- mysterious deaths at the Parakorn Corporation theme park Space
World - featured alien involvement, it was inevitable that Jeremy
would be forced to rise above his original status as he found himself
working with the Third
Doctor, Sarah and The
Brigadier in their latest adventure.

The
Ghosts of N-Space
(Barry Letts)

In many ways, Jeremy was the first companion whose presence was never actually wanted by The Doctor; he would have been perfectly
satisfied with leaving Jeremy on Earth while he and the Brigadier
attempted to track Sarah down after she was abducted by the Parakon
Corporation - revealed to be an alien organisation who were using
an elaborate virtual reality technology to keep the general population
of their world distracted with scenes of wars and hunts - but unfortunately
Jeremy ended up accompanying The Doctor and the Brigadier when they
went to rescue Sarah due to The Doctor asking Jeremy to take his
toolbox into the TARDIS and forgetting to ask him to stop. Despite
the frustration of Jeremy’s presence - with their trek through
a jungle hampered by his complaining more than by the jungle’s
inhabitants - The Doctor, Sarah and the Brigadier nevertheless managed
to defeat the Parakon Corporation by forcing its elderly President
to recognise what his world had become due to him turning a blind
eye to its actions, encouraging him to take action to change its
methods while continuing to help his people.

The Ghosts of N-Space
(Barry Letts)

Jeremy later returned to The Doctor’s life while
The Doctor was investigating the apparent appearance of ghosts at a castle
in Italy belonging to the Brigadier’s his great-uncle Mario, Jeremy
having invited Sarah on holiday with him after his mother fell ill and
left him with an extra ticket. Having determined that the ghosts that appeared
in the castle were the result of it having been built on a fracture in
Null –Space - an alternative dimension where the spirits of the uneasy
dead are trapped, unable to abandon the ties to their earthly lives and
move on to the next level of existence - The Doctor discovered that mobster
Max Vilimo was actually medieval astromancer Maximilian Vilmius, who had
opened the fracture centuries ago while seeking eternal life and power
only to become trapped on the wrong side, and now sought to permanently
escape N-Space while gaining complete control of the N-forms within to
become master of the world. Unlike his last trip in the TARDIS, on this
occasion Jeremy managed to make a positive contribution to their struggle,
taking out a group of Vilimo’s mobsters after they were possessed
by N-forms by shooting one of them while he was hidden, thus provoking
them into attacking and destroying each other while The Doctor cut off
Vilimo’s access to the rift after tricking him into absorbing more
power than he could contain.

Although The Doctor took Jeremy on a couple of solo trips after this incident, such as a trip to the planet Sedna where the ruling Arrangers would only accept meetings with those presented them with art, with Jeremy's poorly-fashioned but enthusiastic work winning the ruling body over due to the passion he put into it while inspiring them to resolve a conflict ("Sedna"), accidents such as Jeremy accidentally trapping a man on a different phase of reality when he triggered a burst of temporal energy while fiddling with the TARDIS controls ("The Dead Man's Story") left The Doctor with a low opinion of his abilities as a long-term companion. When Jeremy later became part of a cult that worshipped an alien gestalt known as the Skang that sought to consume Earth, Sarah only initially investigated his disappearance because his mother asked her directly, with the brainwashed Jeremy only assisting Sarah in her investigations because she tricked him into giving her vital information; Jeremy even seemed to be ignorant that there had been any alien involvement in the cult once the Skang was defeated by The Doctor, simply complaining that he hadn't received the cult's 'reward' (Which would have been to become part of the gestalt) ("Island of Death").

Despite these shortcomings, Jeremy continued to visit UNIT to try and awkwardly flirt with Sarah, culminating in him visiting the base while most of his associates were occupied dealing with the Metebelis spiders ("Planet of the Spiders") and accidentally activating the psychic scanner/enhancer that The Doctor had been using to measure the psychic potential of Professor Clegg. Somehow, Jeremy's exposure to the machine affected his memory, and although the Brigadier discovered him and managed to get him out before it left him a complete vegetable, The Doctor never bothered to check on him to see if he had recovered afterwards because he never particularly liked Jeremy that much. (The distance most likely made worse by The Doctor's subsequent regeneration and the Fourth Doctor's relative indifference to his predecessor's role in UNIT ("Robot" and "Pyramids of Mars"). The machine having left Jeremy totally amnesic, unable even to retain new information such as languages, his only even vague recollections of his past led him to conclude that he had once worked for UNIT, leaving him resolved to find the Brigadier and The Doctor and make them reveal who he was.

Instruments of Darkness
(Gary Russell)

Using the name 'John Doe', the former Jeremy went on to become a wandering vagrant, eventually ending up in Paris where he told anyone who would listen to him various British secrets that randomly emerged from his damaged mind. Having been taken by agents of the Magnate - supposedly a secret criminal society that many believed was running the world - 'John Doe' went on to become the head of a secret organisation called the Network, based underneath Paris and apparently connected to the Magnate, the secret criminal society that many believed was running the world, all the while pursuing his private vendetta against The Brigadier and The Doctor as he searched for them (Evidently totally unaware of The Doctor's ability to regenerate, as he continued to look for the Third Doctor long after UNIT began to work with other Doctors). Despite all his efforts, John Doe never regained more memories than basic flashes in dreams or reality, such as dreaming of the accident where he lost his memories only to forget it after waking up, or once automatically speaking fluent French without realising it; he was apparently even unable to process new information to any real extent, relying on others to translate French for him even after years of living in Paris. Although now a ruthless criminal, Doe still often acted like the immature idiot he'd been when he was Jeremy, regarded by his agents as an upper-class fop and prone to adult tantrums when things didn't go his way; he once even basically condemned ex-RAF pilot Charles Dickinson to death when Dickinson came to Paris to investigate reports that his long-lost son was alive and amnesic simply because he didn't recognise Doe (His son, Justin Dickinson, was actually one of the ESPnet).

Over the subsequent years, the Network gathered together a group of ESPnets - humans with various assorted powerful psychic abilities - using them to run errands while simultaneously claiming that they were being employed by the UN, Doe being the perfect candidate to run such an operation as his brain damage rendered his mind unable to be read by telepaths. Eventually, John Doe's activities brought the Network to the Sixth Doctor's attention in the last few days of 1993, when they abducted Trey Korte - a powerful psychic whose abilities had been activated after an encounter with the TARDIS and an old friend of The Doctor's current companion Melanie Bush - to replace one of their ESPnet. The Doctor, Mel, and former companion Evelyn Smythe - whom The Doctor had left on Earth in 1988 to keep track of a few loose ends due to his own inability to focus on Earth when there were so many other worlds that would require his help - managed to follow Trey's trail to the Irish twins Ciara and Cellian, former agents of a renegade government official who had augmented them into lethal assassins using Auton technology before Trey and The Doctor broke their programming in their last encounter ("Business Unusual"). Seeking redemption for their pasts, the twins were now working with the powerful psychic Sebastian Malvern to stop the true face of the Magnate; alien psychics known as the Cylox, who had been imprisoned in a pocket dimension centuries in the past and now seeking to escape (One of them had managed to physically escape to Earth with more limited powers, requiring the other to astrally project himself to Earth and create the fiction of the Magnate to set up a criminal network that could track down and recapture his brother).

Aided by Malvern, The Doctor was able to defeat the Cylox by triggering the destruction of their dimension and forcing them into another, smaller prison that he created from the remnants of their realm, although a third entity that had been assigned as their warden subsequently destroyed the Cylox. At the same time, however, Malvern was confronted by one of Doe's agents who had long ago been turned into a 'sleeper agent' for one of the Cylox, and although the agent was defeated, Doe followed her to Malvern when she forced one of the ESPnet to teleport her to him to stop him thwarting her master. Refusing to listen to reason, Doe attempted to force Mel and Evelyn to lead him to The Doctor by threatening Malvern and their assorted allies, only for Doe to be shot during the confrontation by Malvern's associates. Shortly before he departed Earth, The Doctor, having seen a picture of Doe, mourned his past dislike of Jeremy, as so much death could have been averted if he'd simply been a bit more interested in the man's fate.